The table shows the decay rate for a certain radioactive material over time. In this context, what does the y-intercept represent? At 100 hours, there are 0 grams of the substance remaining.
At 100 hours, there are 100 grams of the substance remaining.
At 0 hours, there are 100 grams of the substance remaining.
At 0 hours, there is 1 gram of the substance remaining.

It's C

How many triangles can be drawn with side lengths 4 centimeters, 4.5 centimeters, and 9 centimeters? explain

Given sin∅ = 1/3 and 0 < ∅ < π/2 ; find tan2∅ a. (4√2)/9 b. 9/7 c. (4√2)/7 d.7/9

The figure shows triangle def and line segment bc, which is parallel to ef: triangle def has a point b on side de and point c on side df. the line bc is parallel to the line ef. part a: is triangle def similar to triangle dbc? explain using what you know about triangle similarity. part b: which line segment on triangle dbc corresponds to line segment ef? explain your answer. part c: which angle on triangle dbc corresponds to angle f? explain your answer. asap